Holy crap is this a pet peeve of mine. People complaining that they can’t get a good sound for their show or recording, only to discover that they haven’t changed their strings in a year. I think that it seems like a small thing to some people, a thing they just take for granted – guitars/basses have strings on them, you play them til they break, then you take them in to someone who changes them for you.
This is a practice that needs to stop on the immediate. New strings are imperative for getting a good sound out of your instrument (for metal anyway – some jazz guys like a kind of dead string sound for their stuff) – without them, the harmonic content of your tone is reduced to nearly nothing. By itself, it might sound okay, but drop it into a mix and you might as well not even show up to the recording session.
If you don’t believe me, feel free to disagree AFTER watching this video put together by Furious Glenn Fricker. I trust him because in the great white north, there’s nothing better to do than stay inside and test shit like this all day long: